JPH0525877B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to novel hydantoin derivatives. The compound of the present invention is a sensitizer for heat-sensitive recording materials, more specifically, a colorless or light-colored basic dye;
It is extremely useful as a sensitizer used in the heat-sensitive recording layer of a heat-sensitive recording material that utilizes the reaction between the dye and a color developer that develops color upon contact with the dye. [Conventional technology and its problems] Sheet-like base material (paper, polyester sheet, etc.)
A heat-sensitive recording material is provided with a heat-sensitive recording layer containing a basic dye and a color developer that reacts with the dye to develop color when heated, and a surface protective layer is formed as necessary. Widely used in thermal recording devices such as ticket vending machines and various printers. In recent years, as heat-sensitive recording devices have been improved, diversified, and improved in performance, quality requirements for highly sensitive heat-sensitive recording materials capable of high-speed recording have become increasingly strict. Many proposals have been made to use thermofusible substances (fatty acid amides, fats and oils, etc.) as sensitizers in order to improve the sensitivity of heat-sensitive recording materials. However, as the recording sensitivity improves, there are new drawbacks such as a decrease in the stability of the heat-sensitive recording layer, and more specifically, a decrease in whiteness, so it is not always possible to obtain a satisfactory heat-sensitive recording material. It is. [Problems to be solved by the invention and means for solving the same] As a result of various studies in order to develop a heat-sensitive recording material with excellent high-speed recording properties and without drawbacks such as a decrease in whiteness, the present inventor has developed the following general formula (). We have found that hydantoin derivatives are effective when used as sensitizers in heat-sensitive recording materials that utilize the reaction between a colorless or light-colored basic dye and a color developer. That is, the present invention is based on the general formula () (In the formula, R ₁ is a hydrogen atom or a methyl group, and R ₂ is a straight-chain alkyl group having 8 to 18 carbon atoms.) Hydantoin derivatives represented by the formula and sensitized heat-sensitive recording materials containing the compounds as active ingredients The aim is to provide a drug. All of the hydantoin derivatives of the present invention represented by the general formula () are new compounds, and the method for producing them includes, for example, reacting hydantoin with isobutyraldehyde or 2-methyl(n)-butyraldehyde to 5- Isobutylidene (or 2-methylpropylidene) hydantoin or 5
-(2-methylbutylidene)hydantoin is obtained,
There is a method of reacting this with an alkyl halide having 8 to 18 carbon atoms. The reaction between hydantoin and aldehyde is carried out, for example, by the method shown in JP-A-61-27971, that is, in the presence of an amino acid or a salt thereof, in water or an aqueous solution with a pH of 8 to 12 at 40 to 100°C for 1 to 10 hours. The method and reaction of 5-alkylidenehydantoin and alkyl halide are described, for example, in Encycl.Chem.
Tech.2nd Ed.Vol 11 p142 method, namely 5
- An effective method is to react an alkylidenehydantoin with an alkyl halide in a polar aprotic solvent with an alkali such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, etc. at 50 to 150°C for 5 minutes to 3 hours. be. When the novel hydantoin derivatives thus obtained are used as sensitizers in a heat-sensitive recording layer that utilizes the reaction between a colorless or light-colored basic dye and a color developer, two or more types may be used in combination; , fatty acid amides such as stearic acid amide, stearic acid methylene bisamide, oleic acid amide, valmitic acid amide, coconut fatty acid amide, 2,2'-methylene bis(4
-methyl-6-t-butylphenol), 4,
4'-butylidenebis(6-t-butyl-3-methylphenol), 1,1',3-tris(2-methyl-
UV absorption of hindered phenols such as 4-hydroxy-5-t-butylphenol)butane, 2-(2'-hydroxy-5'-methylphenyl)-benzotriazole, 2-hydroxy-4-benzyloxybenzophenone, etc. In addition, various known thermofusible substances can also be used in combination. The amount of the sensitizer having the above-mentioned specific structure used according to the present invention is not necessarily limited, but is generally about 0.10 to 10 parts by weight, preferably about 1.0 to 5.0 parts by weight, per 1 part by weight of the color developer. Used within the range of Examples of the colorless or light-colored basic dyes constituting the recording layer of the heat-sensitive recording material include the following. 3,3-bis(p-dimethylaminophenyl)
-6-dimethylaminophthalide, 3,3-bis(p-dimethylaminophenyl)phthalide, 3-
(p-dimethylaminophenyl)-3-(1,2-
dimethylindol-3-yl)phthalide, 3-
(p-dimethylaminophenyl)-3-(2-methylindol-3-yl)phthalide, 3,3-bis(1,2-dimethylindol-3-yl)-
5-dimethylaminophthalide, 3,3-bis(1,2-dimethylindol-3-yl)-6-
Dimethylaminophthalide, 3,3-bis(9-ethylcarbazol-3-yl)-6-dimethylaminophthalide, 3,3-bis(2-phenylindol-3-yl)-6-dimethylaminophthalide 3-p-dimethylaminophenyl-3-(1
triallylmethane dyes such as -methylpyrrol-3-yl)-6-dimethylaminophthalide, 4,
Diphenylmethane dyes such as 4'-bis-dimethylaminobenzhydryl benzyl ether, N-halophenyl-leucoauramine, N-2,4,5-trichlorophenylleucoauramine, benzoylleucomethylene blue, p-nitrobenzoylleuco Thiazine dyes such as methylene blue, loose spirodinaphthopyran, 3-ethyl-spiro-dinaphthopyran, 3-phenyl-spiro-dinaphthopyran, 3-benzyl-spiro-dinaphthopyran, 3-methyl-naphtho(6'-methoxybenzo) spiropyran , spiro dyes such as 3-propyl-spiro dibenzopyran, rhodamine-B-
Lactam dyes such as anilinolactam, rhodamine (p-nitroanilino)lactam, rhodamine (o-chloroanilino)lactam, 3-dimethylamino-7-methoxyfluorane, 3-diethylamino-6-methoxyfluorane, 3-diethylamino- 7-methoxyfluoran, 3-diethylamino-7-chlorofluoran, 3-diethylamine-6-methyl-7-chlorofluoran, 3-
diethylamino-6,7-dimethylfluorane,
3-(N-Ethyl-p-toluidino)-7-methylfluorane, 3-diethylamino-7-N-acetyl-N-methylaminofluorane, 3-diethylamino-7-N-methylaminofluorane, 3
-diethylamino-7-dibenzylaminofluorane, 3-diethylamino-7-N-methyl-N
-benzylaminofluorane, 3-diethylamino-7-N-chloroethyl-N-methylaminofluorane, 3-diethylamino-7-N-diethylaminofluorane, 3-(N-ethyl-p-toluidino)-6-methyl -7-phenylaminofluorane, 3-(N-ethyl-p-toluidino)-
6-methyl-7-(p-toluidino)fluoran,
3-diethylamino-6-methyl-7-phenylaminofluoran, 3-dibutylamino-6-methyl-7-phenylaminofluoran, 3-diethylamino-7-(2-carbomethoxy-phenylamino)fluoran, 3 -(N-cyclohexyl-N-methylamino)-6-methyl-7-phenylaminofluorane, 3-pyrrolidino-6-methyl-7-phenylaminofluorane, 3-piperidino-6-methyl-7- Phenylaminofluorane, 3-diethylamino-6-methyl-7-xylidinofluorane, 3-diethylamino-7-
(o-chlorophenylamino)fluoran, 3-
Dibutylamino-7-(o-chlorophenylamino)fluoran, 3-pyrrolidino-6-methyl-
7-p-butylphenylaminofluorane, 3-
(N-methyl-Nn-amyl)amino-6-methyl-7-phenylaminofluorane, 3-(N
-ethyl-N-n-amyl)amino-6-methyl-7-phenylaminofluorane, 3-(N-ethyl-N-iso-amyl)amino-6-methyl-
7-Phenylaminofluorane, 3-(N-methyl-N-n-hexyl)amino-6-methyl-7
-phenylaminofluorane, 3-(N-ethyl-N-n-hexyl)amino-6-methyl-7-
Phenylaminofluorane, 3-(N-ethyl-
N-β-ethylhexyl)amino-6-methyl-
7-phenylaminofluorane, 2,2-bis[4-[6'-(N-cyclohexyl-N-methylamino)-3'-methylspiro[phthalide-3,9'-
xanthine]-2'-ylamino]phenyl]propane, 2,2-bis[4-[6'-(N-cyclohexyl-N-methylamino)-3'-methylspiro[phthalide-3,9'-xanthine-2 '-ylamino]phenyl]butane and the like. The color developer used in combination with the above basic dyes is not particularly limited, and should have the property of liquefying, vaporizing, or dissolving when the temperature rises, and should come into contact with the above basic dyes. Various color developers are used that have the property of causing color development. Typical specific examples include 4-tert-butylphenol, α-naphthol, β-naphthol,
4-acetylphenol, 4-tert-octylphenol, 4,4'-sec-butylidenephenol,
4-phenylphenol, 4,4'-dihydroxy-diphenylmethane, 4,4'-isopropylidene diphenol, hydroquinone, 4,4'-cyclohexylidene diphenol, 4,4'-dihydroxydiphenyl sulfide, 4, 4'-thiobis(6-tert-butyl-3-methylphenol),
3,4-dihydroxydiphenyl-p-trisulfone, 3-chloro-4-hydroxydiphenylsulfone, 4,4'-dihydroxydiphenylsulfone, hydroquinone monobenzyl ether, 4-hydroxybenzophenone, 2,4- Dihydroxybenzophenone, 2,4,4'-trihydroxybenzophenone, 2,2',4,4'-tetrahydroxybenzophenone, dimethyl 4-hydroxyphthalate, methyl 4-hydroxybenzoate, 4- Ethyl hydroxybenzoate, propyl 4-hydroxybenzoate, -sec-butyl 4-hydroxybenzoate, pentyl 4-hydroxybenzoate, phenyl 4-hydroxybenzoate, benzyl 4-hydroxybenzoate, tolyl 4-hydroxybenzoate, 4
-chlorophenyl hydroxybenzoate, phenylpropyl 4-hydroxybenzoate, phenethyl 4-hydroxybenzoate, p-chlorobenzyl 4-hydroxybenzoate, p-methoxybenzyl 4-hydroxybenzoate, propyl gallate, gallic acid Phenolic compounds such as lauryl and stearyl gallate, benzoic acid, p-tert-butylbenzoic acid, trichlorobenzoic acid, terephthalic acid, 3
-sec-butyl-4-hydroxybenzoic acid, 3-
Cyclohexyl-4-hydroxybenzoic acid, 3,
5-dimethyl-4-hydroxybenzoic acid, salicylic acid, 3-isopropylsalicylic acid, 3-tert-
Butylsalicylic acid, 3-benzylsalicylic acid, 3
-(α-methylbenzyl)salicylic acid, 3-chloro-5-(α-methylbenzyl)salicylic acid, 3,
5-di-tert-butylsalicylic acid, phenyl-5
-(α,α-dimethylbenzyl)salicylic acid, 3,
Aromatic carboxylic acids such as 5-di-α-methylbenzylsalicylic acid, and these phenolic compounds,
Examples include organic acidic substances such as salts of aromatic carboxylic acids and polyvalent metals such as zinc, magnesium, aluminum, calcium, titanium, manganese, tin, and nickel. The ratio of the basic dye to the color developer is generally 1.0 to 5.0 parts by weight, preferably 1.5 to 3.0 parts by weight, per 1 part by weight of the dye. It should be noted that, of course, two or more of the basic dye and the color developer may be used in combination as necessary. In addition to basic dyes and color developers, inorganic pigments may be added to the heat-sensitive recording material. Examples of inorganic pigments include calcium carbonate, aluminum hydroxide, talc, kaolin, diatomaceous earth, titanium oxide, magnesium carbonate, silicon oxide, and the like. Also,
A dispersion of a salt such as zinc stearate or calcium stearate may be added as appropriate to prevent the recording layer from staking upon contact with a recording head or the like. Furthermore, in order to improve adhesion to substrates such as paper, heat-sensitive recording materials contain binders, and when water is used as a dispersion medium, starches, hydroxycellulose, carboxymethylcellulose, gelatin, casein, polyvinyl alcohol, and styrene-maleic anhydride are used. 2 to 40% by weight of the total solids, preferably 5 to 25% of the acid copolymer etc.
On the other hand, when an organic solvent such as toluene or methyl ethyl ketone is used as a dispersion medium, methyl methacrylate resin or the like can be used in an amount of 10 to 50 weight %, preferably 20 to 40 weight % of the total solid matter. Of course, the binder is not limited to these. Generally known methods can be used to prepare a heat-sensitive recording material using the various heat-sensitive coloring layer forming components described above. For example, a basic dye, a color developer, a thermally fusible substance, an inorganic pigment, and other additives are used alone together with a binder,
Alternatively, the basic dye alone is mixed with the remaining components, added to an aqueous medium together with an aqueous polyvinyl alcohol solution, etc., and pulverized and dispersed using a dispersing machine such as a ball mill or attritor to prepare a coating liquid. Next, the respective dispersions are mixed to prepare a heat-sensitive coloring layer coating solution, which is coated on a support such as paper according to a conventionally known technique and dried. There are no particular limitations on the amount of the coating solution applied to a support such as paper, and it is generally applied in a dry weight range of 2 to 12 g/m ² , preferably 3 to 10 g/m ² . Note that the support is not particularly limited, and paper, synthetic fiber paper, synthetic resin film, etc. can be used as appropriate. Furthermore, it is possible to provide an overcoat layer on the recording layer for the purpose of protecting the recording layer, etc. On the other hand, it is of course possible to provide an undercoat layer on the support. Known technology can be added. [Effects of the Invention] Thus, the heat-sensitive recording material obtained by using the novel hydantoin derivative of the present invention as a sensitizer has excellent high-speed recording properties, and has little reduction in whiteness.
It has a well-balanced quality. [Examples and Usage Examples] Hereinafter, specific examples of the synthesis of the novel hydantoin derivatives of the present invention and usage examples thereof will be described in detail. However, these are examples to facilitate understanding of the present invention, and the present invention is of course not limited to these in any way. Example 1 A 500 ml separable flask equipped with a thermometer, reflux condenser, and stirrer was set in a constant temperature bath. 200ml of water, 50.0g of hydantoin (=0.50mol),
Isobutyraldehyde 72.1g (=1.00mol), glycine 28.1g (=0.38mol), caustic soda 7.5g
(=0.19 mol) and stirred at 70 to 75°C for 7 hours. During this time, the pH of the reaction solution was 9.5 to 9.3. After cooling to room temperature, the crystals were collected by centrifugation to obtain 5-(2-methylpropylidene)-hydantoin.
62.1g was obtained. The yield was 84.5% based on hydantoin. Example 2 In Example 1, 26.8g of alanine was substituted for glycine.
(=0.30mol), caustic soda to calcium hydroxide
8.6g (=0.15mol) of isobutyraldehyde
-Methylbutyraldehyde 64.6g (=0.75mol)
Instead, the mixture was stirred at 80°C for 4 hours. During this time, the pH of the reaction solution was 9.4 to 9.2. After cooling to room temperature,
Crystals were collected by centrifugation to obtain 74.5 g of 5-(2-methylbutylidene)-hydantoin. The yield was 88.6% based on hydantoin. Example 3 A separable flask equipped with a thermometer, reflux condenser, and stirrer was set in a constant temperature bath. 77.0 g (0.50 mol) of 5-(2-methylpropylidene)-hydantoin obtained in Example 1,
DMF400g, n-octadecyl chloride 144.5
g (0.50mol), potassium carbonate 41.5g (0.30mmol)
and stirred at 90 to 100°C for 3 hours. After separating potassium chloride produced by the reaction and unreacted potassium carbonate, DMF was distilled off under reduced pressure to obtain crude yellow crystals. The crude crystals were recrystallized from 300 g of MeOH to obtain 175.8 g of white crystals. (Theoretical quantity 86.2
%) As a result of structural analysis using infrared absorption spectroscopy (IR), mass spectrometry (MS), and other methods, this product was confirmed to be 3-octadecyl-5-(2-methylpropylidene)hydantoin. Melting point 80℃ IR 2920cm ^-1 , 2850cm ^-1 , 1760cm ^-1 , 1720cm ^-1 ,
1680cm ^-1 , 1450cm ^-1 , 720cm ^-1 MS 406, 207, 163, 162, 155, 154, 139 Example 4 In Example 3, n-hexadecyl chloride 130.5 was used instead of n-octadecyl chloride.
The same operation as in Example 3 was performed except that g (0.50 mol) was used. 153.5 g of white crystals were obtained.
(80.8% of the theoretical amount) This product was analyzed in the same manner as above and was confirmed to be 3-hexadecyl-5-(2-methylpropylidene)hydantoin. Melting point 77℃ IR 2920, 2850, 1760, 1720, 1680, 1450, 720 MS 378, 207, 163, 162, 155, 154, 139 Example 5 In Example 3, 5-(2-methylpropylidene)-hydantoin Instead, 5-(2-methylbutylidene)-hydantoin 84 obtained in Example 2
The same operation as in Example 3 was carried out except that 168.0 g of white crystals were obtained (83.6% of the theoretical amount). As a result of the same analysis as above, 3-octadecyl-
It was confirmed to be 5-(2-methylbutylidene)hydantoin. Melting point 73℃ MS 420, 207, 169, 153, 141 Example 6 5-(2-methylbutylidene) obtained in Example 2 instead of 5-(2-methylpropylidene)-hydantoin in Example 3 −Hydantoin
84.0g (0.50mol) of n-hexadecyl chloride instead of n-octadecyl chloride.
The same operation as in Example 3 was carried out except that 130.5 g (0.50 mol) was used, and 150 g of white crystals (80.2% of the theoretical amount) were obtained. ) was confirmed to be a hydantoin. Melting point 69℃ MS 392, 207, 169, 153, 141 Example 7 Melting points (mp) of compounds obtained in the same manner as below
and physical properties such as mass spectra (MS).
Note that the infrared absorption spectra are omitted because there is almost no significant difference between the compounds. (a) 3-position substituent of 5-(2-methylpropylidene)hydantoin n-C ₈ H ₁₇ mp 67℃ MS 266, 163, 162, 155, 154, 139 n-C ₁₀ H ₂₁ mp 68℃ MS 294 , 163, 162, 155, 154, 139 n-C ₁₂ H ₂₃ mp 72℃ MS 322, 207, 163, 162, 155, 154, 139 (b) 3-position substitution of 5-(2-methylbutylidene)hydantoin Group n-C ₈ H ₁₇ mp 55℃ MS 280, 169, 153, 141 n-C ₁₀ H ₂₁ mp 59℃ MS 308, 169, 153, 141 n-C ₁₂ H ₂₃ mp 64℃ MS 336, 207, 169 , 153, 141 Usage example 1 [Dispersion A] 2,2-bis[4-[6'-(N-cyclohexyl-
N-methylamino)-3'-methylspiro[phthalido-3,9'-xanthine]-2'-ylamino]phenyl]propane 25 parts by weight 15% polyvinyl alcohol aqueous solution 25 Water 50 [Dispersion B] 3,4 -Dihydroxyphenyl-p-tolylsulfone 25 parts by weight 15% polyvinyl alcohol aqueous solution 25 Water 50 [Dispersion C] 3-octadecyl-5-(2-methylpropylidene)-hydantoin 25 parts by weight 15% polyvinyl alcohol aqueous solution 25 〃 Water 50 〃 Each of these compositions was ground and dispersed for 24 hours using a paint conditioner to form dispersion A,
B and C were prepared. Next, 10 parts by weight of liquid [A], 25 parts by weight of liquid [B],
[C] 30 parts by weight of liquid, 50% calcium carbonate dispersion 30
parts by weight and 5 parts by weight of 15% polyvinyl alcohol were mixed and stirred to prepare a coating liquid. 50g/m ² of the obtained coating liquid
The dry coating amount is 10 using a wire parr on the base paper.
It was coated and dried at a concentration of g/m ² . Usage example 2 [Acid separation solution D] 3-octadecyl-5-(2-methylbutylidene)
- Hydantoin 25 parts by weight 15% polyvinyl alcohol aqueous solution 25 Water 50 Dispersion [D] was prepared in the same manner as in Use Example 1, and [A]
A thermosensitive recording paper was prepared in the same manner as in Use Example 1 except that 10 parts by weight of liquid, 25 parts by weight of liquid [B], and 30 parts by weight of liquid [C] were used. Usage example 3 [Dispersion E] 2,2-bis[4-[6'-(N-cyclohexyl-
N-methylamino)-3'-methylspiro[phthalido-3,9'-xanthine]-2'-ylamino]phenyl]propane 20 parts by weight Toluene 80 [Dispersion F] Stearyl gallate 25 parts by weight Toluene 75 parts by weight [Dispersion G] 3-hexadecyl-5-(2-methylpropylidene)-hydantoin 25 parts by weight Toluene 75 This composition was ground and dispersed for 24 hours using a paint conditioner to obtain Dispersion E,
Adjusted F and G. Next, 10 parts by weight of liquid [E], 20 parts by weight of liquid [F],
[G] 8 parts by weight of liquid, methyl methacrylate resin
A coating liquid was prepared by mixing and stirring 15 parts by weight of a 20% toluene solution. The resulting coating liquid was applied to a polyethylene terephthalate film using a wire bar until the dry coating amount was 10%.
g/m ² and dried to prepare a heat-sensitive recording film. Comparative Example 1 [C] 3-octadecyl-5- in the adjustment solution
A thermosensitive recording paper was prepared in the same manner as in Use Example 1, except that stearamide was used instead of (2-methylpropylidene)-hydantoin. Comparative Example 2 A thermosensitive recording film was produced in the same manner as in Use Example 3 except that the dispersion liquid [G] was omitted. The five types of heat-sensitive recording materials obtained in this way were tested at a temperature of 110°C using a thermal gradient tester.
A pressure of 1 Kg/cm ² was applied for 0.2 seconds, and the resulting black image was measured using a Macbeth densitometer. Moreover, the whiteness was measured using a Hunter whiteness meter. In addition, in the thermal stability test, the whiteness of the five types of samples obtained was measured using a Hunter whiteness meter after being left at 60°C for 24 hours. The results are shown in Table 1.

[Table] It can be seen that Usage Examples 1 to 3 have a better balance between color density and thermal stability than Comparative Examples 1 and 2.

Claims (1)

[Claims] 1. General formula (In the formula, R ₁ is a hydrogen atom or a methyl group, and R ₂ is a straight-chain alkyl group having 8 to 18 carbon atoms.) A hydantoin derivative represented by the following formula. 2 General formula (In the formula, R ₁ is a hydrogen atom or a methyl group, and R ₂ is a straight-chain alkyl group having 8 to 18 carbon atoms.) A sensitizer for heat-sensitive recording materials containing a hydantoin derivative as an active ingredient.